<template>
  <view>
    <!-- 使用自定义的搜索组件 -->
    <my-search @click="gotoSearch"></my-search>
    <view class="scroll-view-container">
      <!-- 左侧的滚动视图区域 -->
      <scroll-view class="left-scroll-view" scroll-y :style="{height: wh + 'px'}">
        <block v-for="(item, i) in cateList" :key = "i">
          <view :class="['left-scroll-view-item', i === active ? 'active' : '']" @click="activeChanged(i)">{{item.cat_name}}</view>
        </block>
      </scroll-view>
      <!-- 右侧的滚动视图区域 -->
      <scroll-view class="right-scroll-view" scroll-y :style="{height: wh + 'px'}" :scroll-top="scrollTop">
        <view class="cate-lv2" v-for="(item2, i2) in cateLevel2" :key = "i2">
          <!-- 二级分类的标题 -->
           <view class="cate-lv2-title">/ {{item2.cat_name}} /</view>
           <!-- 当前二级分类下的三级分类列表 -->
           <view class="cate-lv3-list">
             <view class="cate-lv3-item" v-for="(item3, i3) in item2.children" :key="i3" @click="gotoGoodsLsit(item3)">
               <image :src="item3.cat_icon.replace('ugo-dev','hmugo-web')"></image>
               <text>{{item3.cat_name}}</text>
             </view>
           </view>
        </view>
        </scroll-view>
    </view>
  </view>
</template>

<script>
  import badgeMix  from '@/mixins/tabbar-badge.js'
  
  export default {
    mixins: [badgeMix],
    data() {
      return {
        //当前设备可用高度
       wh:0,
       //分类列表
       cateList: ['1'],
       //选中分类下标
       active: 0,
       //二级分类
       cateLevel2: [],
       //滚动条距离顶部距离
       scrollTop: 0
      };
    },
    onLoad() {
      const sysInfo = uni.getSystemInfoSync()
      this.wh = sysInfo.windowHeight - 50
      this.getCateList();
    },
    methods:{
      //获取分类列表的数据
      async getCateList() {
        const {data : res} = await uni.$http.get('/api/public/v1/categories');
        if (res.meta.status !== 200) return uni.$showMesg();
        this.cateList = res.message;
        this.cateLevel2 = res.message[0].children
      },
      //点击分类事件
      activeChanged(i) {
        this.active = i
        this.cateLevel2 = this.cateList[i].children
        //scrollTop的值在0和1之间切换
        this.scrollTop = this.scrollTop == 0 ? 1 : 0
      },
      //跳转到商品列表页面
      gotoGoodsLsit(item) {
        uni.navigateTo({
          url:'/subpkg/goods_list/goods_list?cid=' + item.cat_id
        })
      },
      //点击跳转到搜索页面
      gotoSearch() {
        uni.navigateTo({
          url: '/subpkg/search/search'
        })
      }
    }
  }
</script>

<style lang="scss">
  .scroll-view-container{
    display: flex;
    
    .left-scroll-view{
      width: 120px;
      
      .left-scroll-view-item {
        background-color: #f7f7f7;
        line-height: 60px;
        text-align: center;
        font-size: 12px;
        
        &.active {
          background-color: #FFFFFF;
          position: relative;
          &::before{
            content:  ' ';
            display: block;
            width: 3px;
            height: 30px;
            background-color: #c00000;
            position: absolute;
            top:  50%;
            left: 0;
            transform: translateY(-50%);
          }
          
        }
      }
    }
  }
  
  .cate-lv2-title {
    font-size: 12px;
    font-weight: bold;
    text-align: center;
    padding: 15px 0;
    
  }
  .cate-lv3-list {
    display: flex;
    flex-wrap: wrap;
    
    .cate-lv3-item {
      width: 33.33%;
      display: flex;//纵向布局
      flex-direction: column;
       justify-content: center;//纵向居中
       align-items: center;//横向居中
       margin-bottom: 10px;
      image{
        width: 60px;
        height: 60px;
      }
      text{
        font-size: 12px;
      }
    }
  }
</style>
